Chemical Variability of Ivoirian Xylopia rubescens Leaf Oil

Abstract

Forty-two essential oil samples were isolated from leaves of Xylopia rubescens harvested in three forests of Southern Ivory Coast. All the samples have been submitted to GC-FID and the retention indices (RIs) of individual components have been measured on two capillary columns of different polarity. In addition, 20 oil samples, selected on the basis of their chromatographic profile, were also analyzed by C-NMR and 24 components (78.0 - 92.4% of the whole compositions) have been identified. The content of the main components varied drastically from sample to sample: furanoguaia-1,4-diene (5.7 - 54.1%), furanoguaia-1,3-diene (1.1 - 10.5%), (8Z,11Z,14Z)-heptadeca-8,11,14-trien-2-one (4.3 - 16.0%), and (E)-β-caryophyllene (1.7 - 17.3%). Hierarchical cluster and principal components analysis of the 42 oil compositions allowed the distinction of two well-differentiated groups of unequal importance within the oil samples. Oil samples of the main group (Group II) contained mainly furanoguaia-1,4-diene (mean [M] = 43.1%; standard deviation [SD] = 3.2%) while furanoguaia-1,3-diene (M = 8.4%; SD = 0.9%) and (8Z,11Z,14Z)-heptadeca-8,11,14-trien-2-one (M = 7.1%; SD = 1.5%) were present at appreciable contents. The composition of Group I was dominated by furanoguaia-1,4-diene (M = 17.0%; SD = 8.5%), (8Z,11Z,14Z)-heptadeca-8,11,14-trien-2-one (M = 10.2%; SD = 2.4%) and (E)-β-caryophyllene (M = 9.5%; SD = 5.3%).

Composition and Chemical Variability of Ivorian Xylopia rubescens Trunk Bark Oil

“…The compositions of X. rubescens trunk bark oils differed substantially from those of the main group (Group II) of leaf oils characterized by the preeminence of 32 (Mean = 43.1%). In contrast, they resembled to those of Group I that displayed mainly 34 (Mean = 10.2%) beside 32 (Mean = 17.0%) [3]. Finally, there is no correlation between the composition and the location of harvest.…”

“…Oil samples of the major group contained mainly furanoguaia-1,4-diene (Mean = 43.1%). The composition of group I was dominated by furanoguaia-1,4-diene (M = 17.0%), (8Z,11Z,14Z)-heptadec-8,11,14-trien-2-one (M = 10.2%) and (E)-caryophyllene (M = 9.5%) [3]. The composition of the Ivoirian X. rubescens leaf oil differed substantially from oils of other countries, Brazil, for instance (main components, (E)--caryophyllene, bicyclogermacrene and germacrene D) [4].…”

“…Nine trunk bark oil samples isolated from individual trees grown in three Ivorian forests (Yields: 0.01-0.03% w/w vs. fresh material) have been analyzed by GC, on two columns of different polarity, in combination with retention indices, and by 13 C NMR, following a computerized method developed at the University of Corsica [6]. Previous works carried out on the identification of individual components of X. rubescens leaf oil [2,3] demonstrated that all contained furanoguaia-1,4-diene and furanoguaia-1,3-diene among the main components. The furanoguaiadiene isomers were co-eluted on both chromatographic columns and their identification has been achieved by 13 C NMR, while quantitative determination has been carried out by combination of GC(FID) and 13 C NMR.…”

“…Furanoguaia-1,4-diene, its isomer furanoguaia-1,3-diene as well as (8Z,11Z,14Z)-8,11,14-heptadeca-trien-2-ol have been isolated and their structure elucidated [2]. Recently, 42 oil samples were isolated from leaves of X. rubescens harvested in three forests of Côte d'Ivoire [3]. Statistical analysis allowed the distinction of two well differentiated groups.…”